MR Dampers: Advancing Structural Control for Resilient and Sustainable Structures
Structural control is a field dedicated to enhancing the effectiveness and safety
of civil engineering structures, including buildings, bridges, and other edifices.
It employs a range of control techniques to mitigate the impact of environmental forces
such as earthquakes, wind, and other natural hazards, which can compromise the stability
and functionality of these structures. Passive control systems, such as tuned mass
dampers, active control systems involving sensors and actuators, and hybrid control
systems that combine both passive and active techniques are among the methodologies
used in structural control research. The ultimate goal is to increase the resilience
and durability of structures while ensuring the protection of individuals and assets
in the built environment.
Magneto-rheological (MR) dampers have recently garnered renewed interest in structural control research due to their low-power requirements and fail-safe properties. They offer a compelling means of safeguarding civil infrastructure systems from severe earthquakes and wind loading. Various approaches have been proposed to govern MR dampers. This research study demonstrates that the shear response and flexural response of buildings present two distinct cases for vibration suppression. Thus, new bracing-lever mechanism configurations for the dampers are suggested to optimize their performance. The findings illustrate how these proposed arrangements facilitate the application of flexural response in situations where the inter-story drift is insufficient for the dampers to function optimally.
Recent investigations into earthquake-resistant structures have highlighted the exceptional controllability of magnetorheological (MR) dampers. The controllable nature of MR dampers enables the achievement of various control objectives through different control algorithms, including reducing floor displacements, drifts, and absolute accelerations. However, there remains ample potential for further research in developing new controllers in this area, providing researchers with opportunities to explore novel methodologies.
The application of smart dampers for vibration attenuation in civil engineering structures has shown promise in recent years. However, evaluating the efficacy of smart dampers in multiple-degree-of-freedom (MDOF) dynamic systems has proven to be time-consuming. This challenge hinders the ability to consider potential families of controllers for a reliable design and tuning process. To address this, we propose a novel probabilistic approach that enables the analytical solution of highly nonlinear control systems. Unlike current simulation methods, the proposed probabilistic approach significantly reduces computational efforts. Thus, it becomes invaluable in designing and evaluating the effectiveness of smart dampers in MDOF systems, including multistory buildings and wind turbines. Furthermore, the developed control theory enables the use of accelerated performance-based semiactive controller tuning, which has the potential to advance innovative technologies for building smart, resilient, and sustainable structures capable of withstanding multiple hazards.
By combining MR dampers, advanced control algorithms, and probabilistic approaches, our research aims to revolutionize structural control, fostering the development of resilient and sustainable structures that can withstand the challenges posed by natural hazards.
Selected Publications
- Aly, A.M. (2024) "Effects of Bracing Stiffness and Viscoelastic Damping on Enhancing Vibration Control in Buildings," ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part A: Civil Engineering, Accepted.
- Rezaee, M., Aly, A.M. (2019), "Proposed Theory of Semiactive Gains for Smart Dampers in MDOF Systems," Journal of Structural Engineering, ASCE, 145(12). DOI: 10.1061/(ASCE)ST.1943-541X.0002453
- Rezaee, M., Aly, A.M. (2018), "Vibration Control in Wind Turbines to Achieve Desired System-Level Performance under Single and Multiple Hazard Loadings," Structural Control and Health Monitoring, 25(12), e2261. DOI:10.1002/stc.2261
- Aly, A.M. (2016), "The Use of Bracing Systems with MR Dampers in Super Tall Buildings", International Journal of High-Rise Buildings (IJHRB), 5(1), 31-41.
- Aly, A.M., (2015), "Control of wind-induced motion in high-rise buildings with hybrid TM/MR dampers", Wind and Structures, 21(5), 565-595.
- Aly, A.M. "Vibration Control of Buildings Using Magnetorheological Damper: A New Control Algorithm," Journal of Engineering, Volume 2013, Article ID 596078, 10 pages, 2013. DOI: http://dx.doi.org/10.1155/2013/596078